Table 1 Biofilm COMSTAT flow cell measurements for E. coli BW25113 and its isogenic mutants LB glu medium at 24 h and for the dual species (E. coli/P. fluorescens) biofilm in LB medium after 5 days

Single species of BW25113 and its isogenic mutant

BW25113

9 ± 5

8 ± 9

24 ± 8

0.6 ± 0.4

BW25113 with DMF (control for indole)

6.4 ± 3

6.5 ± 7

21 ± 8

0.5 ± 0.5

BW25113 with 500 μM indole

4 ± 1.5

18 ± 6

25 ± 6

0.9 ± 0.6

BW25113 trpE

30 ± 7

13 ± 6

46 ± 3.5

0.3 ± 0.1

Dual species with TOM

P. fluorescens 2-79TOM/pHKT3

0.06 ± 0.05

0.90 ± 0.56

0.14 ± 0.13

1.97 ± 0.02

E. coli K-12 XL1-Blue/pCM18

6.63 ± 2.67

21.52 ± 10.49

13.95 ± 5.67

0.90 ± 0.34

Dual species without TOM

P. fluorescens 2-79/pHKT3

0.03 ± 0.01

0.64 ± 0.16

0.04 ± 0.02

1.99 ± 0.01

E. coli K-12 XL1-Blue/pCM18

0.56 ± 0.51

1.81 ± 1.23

1.04 ± 0.68

1.87 ± 0.06